Since emerge is the Gentoo package manager, these instructions are unlikely to work on any other distro/OS unless of course you have installed prefixed portage.

You need to unmask several packages, by putting the following in /etc/portage/package.keywords to run the 'unstable' branch. Note that these are actually developed in the haskell overlay before moving to the portage tree.

If you're currently running stable ghc, you should upgrade ghc first and then run ghc-updater. Either way, it would be good to emerge ghc first, then emerge himerge.

[edit]3.3 Every time I try to search for a package I receive the 'Package not found' error

Himerge uses eix for searching packages in the tree, so every time you sync, you also need to update the eix database. After a sync just do Ctrl+U or go to the "Tools -> Update Eix" option in the main menu bar to solve it.

Note: The eix database is automatically updated after every sync operation since Himerge version 0.17.3.

Himerge uses the gecko engine of gtkmozembed internally for the web panel, which makes firefox or firefox-alike packages a requirement for the system, so it makes sense to have firefox as the default browser.

Note: Since version 0.30 you can specify the web browser you want to use for opening the web links, using the command line flag '--webrowser'. Notice how you still need firefox or xulrunner installed since it is needed for the gecko engine.

[edit]3.6 Why do I need to click twice on the packages web link to launch the browser?

This is a work-around due to a gtkmozembed bug, probably related to gtk2hs too. The problem has already been reported and probably will have a fix in the near future.

[edit]3.7 The toolbar buttons title doesn't shows and I get an 'sh: kde-config: command not found' everytime I start Himerge

This is a qt-engine known issue that affects gtk. The solution is to change the gtk-engine you are using to other different than 'qt' or 'qt-curve'.